Re: [rules-users] Defeasible: NPE: with multiple @Defeasible

Hi Davide, I've got a null pointer exception with defeasible. My test case is: package com.sample declare Fact fact: String @key end rule init when then System.out.println("inserting initial facts"); insert( new Fact( "one" ) ); insert( new Fact( "two" ) ); insert( new Fact( "two" ) ); end rule rule1 @Defeasible enabled true when Fact( "one"; ) then System.out.println("one causes wibble"); insertLogical( new Fact( "wibble") ); end rule rule2 @Defeasible when Fact( "two"; ) then System.out.println("two causes wibble"); insertLogical( new Fact( "wibble") ); end rule rule3 @Defeater @Defeats( "rule2" ) when Fact( "two"; ) then System.out.println("two negates wibble"); insertLogical( new Fact( "wibble"), "neg" ); end The output I get is inserting initial facts one causes wibble two causes wibble two causes wibble two negates wibble two negates wibble Exception executing consequence for rule "rule3" in com.sample: java.lang.NullPointerException at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39) at org.drools.core.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1057) at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:152) at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:94) at org.drools.core.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:964) at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1234) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1239) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1212) at com.sample.DroolsTest.main(DroolsTest.java:21) Caused by: java.lang.NullPointerException at org.drools.core.beliefsystem.defeasible.DefeasibleBeliefSet.removeUndefeated(DefeasibleBeliefSet.java:295) at org.drools.core.beliefsystem.defeasible.DefeasibleBeliefSet.add(DefeasibleBeliefSet.java:126) at org.drools.core.beliefsystem.jtms.JTMSBeliefSystem.insert(JTMSBeliefSystem.java:52) at org.drools.core.beliefsystem.defeasible.DefeasibleBeliefSystem.insert(DefeasibleBeliefSystem.java:45) at org.drools.core.common.TruthMaintenanceSystem.addLogicalDependency(TruthMaintenanceSystem.java:136) at org.drools.core.common.TruthMaintenanceSystem.addLogicalDependency(TruthMaintenanceSystem.java:107) at org.drools.core.common.NamedEntryPoint.insert(NamedEntryPoint.java:234) at org.drools.core.impl.StatefulKnowledgeSessionImpl.insert(StatefulKnowledgeSessionImpl.java:1430) at org.drools.core.base.DefaultKnowledgeHelper.insertLogical(DefaultKnowledgeHelper.java:275) at org.drools.core.base.DefaultKnowledgeHelper.insertLogical(DefaultKnowledgeHelper.java:247) at com.sample.Rule_rule32132126114.defaultConsequence(Rule_rule32132126114.java:8) at com.sample.Rule_rule32132126114DefaultConsequenceInvokerGenerated.evaluate(Unknown Source) at com.sample.Rule_rule32132126114DefaultConsequenceInvoker.evaluate(Unknown Source) at org.drools.core.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1046) ... 7 more I believe I am using snapshot 6.1.0.201407170510 but I suspect the precise version doesn't matter too much. In the above example, if you disable rule1 then the NPE doesn't happen. Only doing one "two" fact insertion in the init rule likewise means the NPE doesn't happen. I think the issue is something like rule3 does more than one defeat on rule2's scoring on "wibble" fact, but rule1 still has a say in the continuing existence of the "wibble" fact. Should I get a Jira log in and enter these well qualified bugs directly? Regards, Borris _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users